Combined analysis of EDMs and Lepton Flavor Violating rare

decays

YASAMAN FARZAN

IPM, Tehran

Manifestation of heavy states

Direct production at acceleratorsIndirect effects in low energy phenomena

Historic example: Beta decay is the indirect manifestation of W-boson.

Beta decay was discovered in the late 19th century.Direct production of W boson took place only in 1980’s.

Models predicting heavy states SUSY models Extra dimensions various Higgs models …

All these models predict heavy particles to be directly produced at LHC….

Indirect Effects in Low Energy Experiments

Lepton Flavor Violating (LFV) processes:

Magnetic Dipole Moment:

Electric Dipole Moments (EDMs)…..

In this talk, we shall focus on LFV and EDMs and theirCombined analysis.

In parallel to the progress in the high energy frontier (via LHC and hopefully via ILC), in upcoming years we expect breakthrough in the low energy experiments, too.

Unlike the historic example of beta decay and W-boson discovery, in the present era, progressin both directions (low energy and high energy) takes place simultaneously.

Complementary information can be derived by combining the results.

Limitations of LHCSuppose SUSY (or some other BSM) is discoveredat LHC. Little or none can be learned about the the CP-violating phases in the lepton sector at LHC (see however, Godbole Czech J Physc 55; Heinemeyer and Velasco, hep-ph/0506267; Kittel, hep-ph/0504183 ). ILCMeasuring CP-violation Low energy experimentsSearches for EDMs can teach us about the CP-violating phases

EDM and MDM under CP

CP:

CP:

MDM conserves CP but EDM violates CP.

Present bound and prospects for improvement

Present bound: [PDG]

Near future: DeMille et al

Foreseeable future: Lamoreaux, nucl-ex/0109014(employing solid state techniques; Shapiro’s old idea) The phase of CKM: The phases of PMNS: de Gouvea, Gopalakrishna, PRD72Positive signal New Physics

Importance of CP-violationAmong all the parameters of a theory, CP-violating phases hold a place of honor because CP-violation is one of the three famous Sakharov’s conditions for dynamically creating the Baryon asymmetry of the universe.The CP-violating phase that we would measure in the labs might be in the heart of the fundamental question why our body as well as the whole universe around us (so far explored) is made of matter rather than anti-matter.

Which phase is responsible for baryogenesis?

In the framework of some models, the CP-violating phase that is responsible for baryogenesis can also show up in the EDM; e.g., (the phase of bilinear Higgs term in the superpotential ) which leads to both Electroweak baryogenesis and EDM.

Not all the CP-violating phases contributing to EDM can lead to successful baryogenesis. To disentangle the different contributions and to pinpoint the effect of the mu-term, one has to work out all the phases.

Neutrino oscillationThe only evidence so far for physics BSM comes from observation of neutrino oscillation. Contribution of neutrino masses to LFV processes:

Petcov Sov J. NP25; Bilenky et al, PLB67; Altarelli et al, NPB125

PDG

Positive signal in future Physics BSM

Benerjee, hep-ex/0702017

LFV and CP-violation in MSSM

at one-loop

Strong bounds on

Effect of on NO LFV No one loop contributionTwo-loop effect exists but the effect is suppressed.LFV:

To have sizeable effect, and have to be both relatively large.

Ayazi and Farzan, JHEP0706

Present bounds on and prospects for improvements Banerjee, hep-ex/0702017

Super B-factory (physics/0512235)

Other effects of complex

Complex does not contribute to Baryogenesis.

Phase of can manifest itself in decay and production of staus and can in principle be measuredat ILC. Gajdosik, Godbole and Kraml, JHEP 0409; Bartl et al., PRD66

It will be exciting to derive complementary information on this phase from low energy experiments.

Condition for sizeable effect

If orthe contribution of to is suppressed evenif is close to its present bound and is large.

Contribution of the phase of

Left-right ratioSuppose in future is detected.Q: Is there a way to extract ? A: Yes, by studying the angular distribution of the final particles:

is the angle between the spin of tau and the momentum of the emitted

Measurement and interpretation of

By studying the angular distributions of the final particlesat an collider such as B-factory, it will be possibleto extract the value of . Kitano and Okada, PRD63 (2001) 113003

Interpretation of :

or

Present bound

Near Future reach

Correlation of and

The dots depicted by the same color and symbol in the two panels correspond to the same scatter point

All other phases=0

Present bound

Near Future reach

Correlation of and

In the case of the purple dots for which regardless of electron EDM is very small and below the reach of the current experiments.

Present bound

Near Future reach

Correlation of and

For (to be tested by super B-factory) regardless of the value of , is smaller than the present bound.

Present bound

Near Future reach

Correlation of and

If and , there is a good chance of detecting in near future (blue dots) provided that is sizable .

Conclusions By combining the information from

LFV and EDMexperiments, valuable information can

be derived on CP-violationwhich can be considered

complementary to or a cross check of the CP study at ILC.